Mozilla, keeping pace with their regular rapid release schedule, released an update for Firefox Beta today. v39 graduated to stable, sending v40 to the beta channel. With some focus on changes to the desktop version, there aren't major user-facing changes in this Android update. Still, there should be some performance enhancements along with a nice UI improvement for navigating forward and backwards through a tab's history.

The overflow menu has been home to the forward and back shortcuts for quite a while now, but there wasn't an efficient way to navigate by several pages. Starting with v40, pressing and holding on the forward or back arrow will bring up a list view of your history. See below for how this works.

Little tweaks like this can go a long way.

Other changes include better looking CSS animations by making them asynchronous, which may be noticeable for those who were using v39 before. Support for the Presentation API has been added, which is used for sharing via Miracast and the like (Chromecast support has already been present). JPEGs are now rendered more quickly and will use less memory when scaled down. Like I said, this isn't exactly a game-changing release.